Channel detection apparatus and method, user equipment, and base station

ABSTRACT

Disclosed are a channel detection apparatus and method, as well as a user equipment and a base station comprising the channel detection apparatus. The channel detection apparatus is used for performing channel detection over a plurality of carriers in an unlicensed frequency band, and comprises at least one processing circuit. The plurality of carriers comprise a first carrier and a second carrier. The processing circuit is configured to: perform channel detection of whether a channel is idle on the first carrier; and trigger, when it is detected that the channel is occupied during the channel detection on the first carrier, channel detection of whether a channel is idle on the second carrier.

This application claims the priority to the Chinese Patent ApplicationNo. 201610074262.1, titled “CHANNEL DETECTION APPARATUS AND METHOD, USEREQUIPMENT AND BASE STATION” and filed with the Chinese StateIntellectual Property Office on Feb. 2, 2016, which is incorporatedherein by reference in its entirety.

FIELD OF THE INVENTION

The embodiments of the present disclosure generally relate to the fieldof wireless communications, and particularly to carrier scheduling andchannel detection in an unlicensed frequency band in a wirelesscommunication system, and more particularly to a device and a method fora wireless communication system, a spectrum management device, a channeldetection device and a channel detection method, and user equipmentincluding the channel detection device and a base station including thechannel detection device.

BACKGROUND OF THE INVENTION

More and more services are carried in the wireless network withdevelopment and evolution of a wireless network, and therefore, extraspectrum resources are required to support a large amount of datatransmission. The spectrum resources may be characterized by for exampleparameters such as time, frequency, bandwidth, maximum allowableemission power and so on. Limited spectrum resources have been allocatedto fixed operators and services. New available spectrum is very rare orexpensive. In this case, a concept of dynamic spectrum usage isproposed, that is, spectrum resources which have been allocated to somesystems or services but are not used sufficiently are used dynamically.The spectrum resources are unlicensed for a system which uses thespectrum resources dynamically. A wireless communication systemdetermines whether an unlicensed frequency band is available beforeusing the unlicensed frequency band. Since communication systems ofdifferent operators and communication systems under differentcommunication protocols have equal rights to use the unlicensedfrequency band, a problem urgent to be solved in the industry is how touse transmission resources of the unlicensed frequency band fairly andeffectively.

SUMMARY OF THE INVENTION

In the following, an overview of the present invention is given simplyto provide basic understanding to some aspects of the present invention.It should be understood that this overview is not an exhaustive overviewof the present invention. It is not intended to determine a criticalpart or an important part of the present invention, nor to limit thescope of the present invention. An object of the overview is only togive some concepts in a simplified manner, which serves as a preface ofa more detailed description described later.

According to an aspect of the present disclosure, there is provided adevice for a wireless communication system, which includes at least oneprocessing circuit configured to: generate, for at least one group ofcarriers in an unlicensed frequency band, at least one set of channeldetection parameters for use by user equipment to detect whether achannel is idle, wherein the at least one group of carriers are acquiredby grouping at least a part of carriers in the unlicensed frequencyband; generate carrier grouping information indicating a result of thegrouping of the carriers; and generate an uplink scheduling grant forthe at least one group of carriers.

According to another aspect of the present disclosure, there is provideda device for a wireless communication system, which includes at leastone processing circuit configured to: determine, based on carriergrouping information for an unlicensed frequency band and an uplinkscheduling grant for the unlicensed frequency band received from a basestation, a group of carriers on which channel detection is to beperformed; and perform channel detection on a carrier in the determinedgroup of carriers using channel detection parameters received from thebase station.

According to another aspect of the present disclosure, there is provideda spectrum management device, which includes: at least one processingcircuit, configured to group carriers in an unlicensed frequency band;and a transmitting unit, configured to provide carrier groupinginformation on the grouping of the carriers to a base station.

According to another aspect of the present disclosure, there is provideda method for a wireless communication system, including: for at leastone group of carriers in an unlicensed frequency band, generating atlast one set of channel detection parameters for use by user equipmentto detect whether a channel is idle, wherein the at least one group ofcarriers are acquired by grouping at least a part of carriers in theunlicensed frequency band; generating carrier grouping informationindicating a result of the grouping of the carriers; and generating anuplink scheduling grant for the at least one group of carriers.

According to another aspect of the present disclosure, there is provideda method for a wireless communication system, including: determining,based on carrier grouping information for an unlicensed frequency bandand an uplink scheduling grant for the unlicensed frequency bandreceived from a base station, a group of carriers on which channeldetection is to be performed; and performing channel detection on acarrier in the determined group of carriers using channel detectionparameters received from the base station.

According to yet another aspect of the present disclosure, there isprovided a channel detection device for performing channel detection onmultiple carriers in an unlicensed frequency band, which includes atleast one processing circuit. The multiple carriers include a firstcarrier and a second carrier. The processing circuit is configured toperform channel detection of whether a channel being idle on the firstcarrier, and trigger channel detection of whether a channel being idleon the second carrier in a case that it is detected during the channeldetection on the first carrier that the channel is occupied.

According to another aspect of the present disclosure, there is provideda channel detection method for performing channel detection on multiplecarriers in an unlicensed frequency band. The multiple carriers includea first carrier and a second carrier. The channel detection methodincludes: performing channel detection of whether a channel being idleon the first carrier, and triggering channel detection of whether achannel being idle on the second carrier in a case that it is detectedduring the channel detection on the first carrier that the channel isoccupied.

According to another aspect of the present disclosure, there is furtherprovided user equipment including the channel detection device describedabove and a base station including the channel detection devicedescribed above.

According to another aspect of the present disclosure, there is furtherprovided user equipment including the channel detection device forperforming channel detection on multiple carriers in an unlicensedfrequency band. The channel detection device includes at least oneprocessing circuit. The multiple carriers are grouped into multiplegroups of carriers, and each group of carriers includes at least onefirst carrier and at least one second carrier. The processing circuit isconfigured to: perform channel detection of whether a channel being idleon the first carrier in each group of carriers, and trigger channeldetection of whether a channel being idle on the second carrier in thegroup of carriers in a case that it is detected during the channeldetection on the first carrier in the group of carriers that the channelis occupied.

According to other aspects of the present disclosure, there are alsoprovided computer program codes and computer program products forimplementing the method for the wireless communication system and thechannel detection method described above, and a computer readablestorage medium, on which the computer program codes for implementing themethod for the wireless communication system and the channel detectionmethod described above are recorded.

In the embodiments of the present disclosure, the carriers in theunlicensed frequency band are grouped and an uplink scheduling grantcorresponding to each group of carriers is generated, thereby improvingusage efficiency of resources in the unlicensed frequency band. Inaddition, cascaded channel detection is performed on multiple carriers,thereby reducing calculation complexity.

These and other advantages of the present disclosure will be moreapparent by illustrating in detail a preferred embodiment of the presentinvention in conjunction with accompanying drawings below.

BRIEF DESCRIPTION OF THE DRAWINGS

To further set forth the above and other advantages and features of thepresent invention, detailed description will be made in the followingtaken in conjunction with accompanying drawings in which identical orlike reference signs designate identical or like components. Theaccompanying drawings, together with the detailed description below, areincorporated into and form a part of the specification. It should benoted that the accompanying drawings only illustrate, by way of example,typical embodiments of the present invention and should not be construedas a limitation to the scope of the invention. In the accompanyingdrawings:

FIG. 1 is a structural block diagram of a device for a wirelesscommunication system according to an embodiment of the presentdisclosure;

FIG. 2 is a block diagram of another structure example of a processingcircuit shown in FIG. 1;

FIG. 3 is a schematic diagram showing an example of a type of the energydetection;

FIG. 4 shows an example of a signaling configuration of carrier groupinginformation and energy detection parameters;

FIG. 5 is a block diagram of another structure example of a processingcircuit shown in FIG. 1;

FIG. 6 is a structural block diagram of a channel detecting unitaccording to an embodiment of the present disclosure;

FIG. 7 shows an example of an operation of a channel detecting unit;

FIG. 8 is a structural block diagram of a device for wirelesscommunication according to an embodiment of the present disclosure;

FIG. 9 is a schematic diagram showing a transmission example in a casethat uplink scheduling grants for two groups of carriers are received;

FIG. 10 is a block diagram of another structure example of theprocessing circuit shown in FIG. 8;

FIG. 11 is a structural block diagram of a channel detecting unitaccording to an embodiment of the present disclosure;

FIG. 12 shows an example of an operation of a channel detecting unit;

FIG. 13 is a structural block diagram of a spectrum management deviceaccording to an embodiment of the present disclosure;

FIG. 14 is a structural block diagram of a channel detection deviceaccording to an embodiment of the present disclosure;

FIG. 15 is a flowchart of a method for wireless communications accordingto an embodiment of the present disclosure;

FIG. 16 is a flowchart of a method for wireless communications accordingto an embodiment of the present disclosure;

FIG. 17 is a flowchart of a channel detection method according to anembodiment of the present disclosure;

FIG. 18 shows an example of an information flow between a base stationand a user equipment;

FIG. 19 shows another example of an information flow between a basestation and a user equipment;

FIG. 20 shows another example of an information flow between a basestation and a user equipment;

FIG. 21 is a block diagram illustrating a first example of a schematicconfiguration of an evolved Node B (eNB) to which the technology of thepresent disclosure may be applied;

FIG. 22 is a block diagram illustrating a second example of a schematicconfiguration of an eNB to which the technology of the presentdisclosure may be applied;

FIG. 23 is a block diagram illustrating an example of a schematicconfiguration of a smart phone to which the technology of the presentdisclosure may be applied;

FIG. 24 is a block diagram illustrating an example of a schematicconfiguration of an car navigation device to which the technology of thepresent disclosure may be applied; and

FIG. 25 is a block diagram of an exemplary block diagram illustratingthe structure of a general purpose personal computer capable ofrealizing the method and/or device and/or system according to theembodiments of the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

An exemplary embodiment of the present invention will be describedhereinafter in conjunction with the accompanying drawings. For thepurpose of conciseness and clarity, not all features of an embodimentare described in this specification. However, it should be understoodthat multiple decisions specific to the embodiment have to be made in aprocess of developing any such embodiment to realize a particular objectof a developer, for example, conforming to those constraints related toa system and a business, and these constraints may change as theembodiments differs. Furthermore, it should also be understood thatalthough the development work may be very complicated andtime-consuming, for those skilled in the art benefiting from the presentdisclosure, such development work is only a routine task.

Here, it should also be noted that in order to avoid obscuring thepresent invention due to unnecessary details, only a device structureand/or processing steps closely related to the solution according to thepresent invention are illustrated in the accompanying drawing, and otherdetails having little relationship to the present invention are omitted.

First Embodiment

FIG. 1 is a structural block diagram of a device 100 for a wirelesscommunication system according to an embodiment of the presentdisclosure, and the device 100 includes at least one processing circuit101 configured to: generate, for at least one group of carriers in anunlicensed frequency band, at least one set of channel detectionparameters for use by user equipment to detect whether a channel isidle, wherein the at least one group of carriers are acquired bygrouping at least a part of carriers in the unlicensed frequency band;generate carrier grouping information indicating a result of thegrouping of the carriers; and generate an uplink scheduling grant forthe at least one group of carriers. The device 100 may be located forexample at a network management side such as a base station of thewireless communication system.

In the present disclosure, there is considered a correspondencerelationship between channels and carriers, that is, one carriercorresponds to one channel. Detection on a carrier is referred to aschannel detection. In a case that a carrier is not occupied, the carrieris considered as idle and a channel corresponding to the carrier isidle. The carrier and the channel are not distinguished in particular inthe description hereinafter.

In addition, FIG. 1 further shows an example of functional modules of aprocessing circuit 101. As shown in FIG. 1, the processing circuit 101includes a channel detection parameter generating unit 1001, a groupinginformation generating unit 1002 and an uplink scheduling grantgenerating unit 1003. It should be understood that the functionalmodules may be implemented by processing circuits respectively, or mayall be implemented by one processing circuit, or may be implemented as apart of a processing circuit. Alternatively, each of the functionalmodules may be implemented by multiple processing circuits. In otherwords, implementation of the functional modules is not limited. Theprocessing circuit 101 may be for example a central processing unit(CPU), a microprocessor, an integrated circuit module and the like withdata processing capability. A structure and a function of the device 100are described in detail below with reference to FIG. 1.

In an LTE communication system, user equipment should acquire an uplinkscheduling grant from a base station before communicating in anunlicensed frequency band, and performs channel detection upon receivingthe uplink scheduling grant to determine whether a scheduled channel isidle. The user equipment may perform data transmission using thescheduled uplink transmission resources only in a case that the channelis idle. However, it is possible during the channel detection that thescheduled carrier is occupied while there may be another idle carrierwhich is not scheduled. It is desirable to raise a probability that thescheduled carrier can be used for uplink transmission, so as to improveusage efficiency of resources in the unlicensed frequency band.

It should be understood that although the technology is described withrespect to the LTE communication system, the technology is alsoapplicable to the future 5G or even a more advanced wirelesscommunication system.

In the present disclosure, the base station may transmit multiple uplinkscheduling grants to the user equipment, so that the user equipment canperform uplink data transmission using multiple carriers (that is,carrier aggregation in the unlicensed frequency band). In this way,communication quality and capacity of data transmission of the userequipment in the unlicensed frequency band are improved.

In another aspect, in the embodiment, at least a part of carriers in theunlicensed frequency band are grouped, to obtain at least one group ofcarriers. Uplink scheduling is performed on a group of carriers ratherthan a single carrier, thereby raising a probability that the scheduledcarrier can be used for uplink transmission. The number of groups ofcarriers is determined based on for example transmission capability ofthe user equipment itself or the number of carriers to be simultaneouslyused for uplink transmission. Specifically, in a case that the userequipment is to perform uplink transmission with N carrierssimultaneously, N groups of carriers may be obtained. Each group ofcarriers includes for example three carriers, and the number of carriersin each group of carriers may be set based on for example the number ofcontinuous available carriers in the unlicensed frequency band or thelike.

For example, the processing circuit 101 may be further configured togroup carriers in the unlicensed frequency band. Correspondingly, asshown in FIG. 2, the processing circuit may further include a carriergrouping unit 1004 configured to group the carriers in the unlicensedfrequency band. For example, the processing circuit 101 is configured togroup the carriers in the unlicensed frequency band into multiple groupsof carriers.

The carrier grouping unit 1004 may group all carriers in the unlicensedfrequency band, or just group a part of the carriers in the unlicensedfrequency band. For example, in a case that there are 32 carriers intotal and four groups of carriers are required, the 32 carriers may begrouped into four groups of carriers, and each group of carriersincludes eight carriers. Alternatively, in consideration of complexityof channel detection, only 12 carriers among the 32 carriers may beselected, and are grouped into four groups of carriers.

As an example, the carrier grouping unit 1004 may group the carriersbased on at least one of a frequency band location of each carrier, ausage status of each carrier, an amount of data to be transmitted foreach service of the user equipment, and information in a geographicallocation database. The amount of data to be transmitted for each serviceof the user equipment may be acquired for example based on a bufferstatus report (BSR). From another perspective, the carrier grouping unit1004 may group the carriers based on information in the BSR uploaded bythe user equipment.

For example, in a case that frequency band locations of two carriers areclose or adjacent to each other, channel characteristics of the twocarriers may be similar, and therefore, the two carriers may be groupedinto the same group. In addition, the usage status of a carrierindicates a load status on the carrier, for example, a carrier withlight load may be selected to be grouped. In another aspect, forexample, when the amount of data to be transmitted by the user equipmentis large, a carrier with light load may be selected to be grouped. Inaddition, the carrier grouping unit 1004 may also take a geographicallocation of the user equipment into consideration by referring toinformation in the geographical location database. For example, in acase that a user equipment which uses a carrier to perform datatransmission is far away from a user equipment for which uplinktransmission resources are scheduled currently, the carrier may beselected. It should be illustrated that frequency locations of carriersin each group of carriers may be continuous, or may be discrete.

Exemplarily, the usage status of each carrier may be obtained with atleast one of the following manners: being measured by a base station,being provided by a related spectrum management device, and beingprovided by a geographical location database.

In an example, the carrier grouping unit 1004 may group the carriers byselecting a primary carrier and then selecting a secondary carrierallocated to the primary carrier, wherein a priority level for the userequipment to use the primary carrier to perform data transmission ishigher than a priority level for the user equipment to use the secondarycarrier to perform data transmission. In practice, the carrier groupingunit 1004 may group the carriers in another manner, which is notlimited. For example, carriers to be grouped into the same group areselected first, and then a primary carrier and a secondary carrier arespecified.

Correspondingly, the grouping information generating unit 1002 generatescarrier grouping information indicating a result of the grouping thecarriers, such as information indicating carriers in each group ofcarriers. In an example, the carrier grouping information may includeinformation indicating a group to which a carrier belongs, andinformation indicating whether the carrier is a primary carrier or asecondary carrier in the group. For example, assuming that a group ofcarriers includes a carrier 1, a carrier 2 and a carrier 3, and thecarrier 1 is a primary carrier and the carrier 2 and the carrier 3 aresecondary carriers, the carrier grouping information may include: acarrier 1→a primary carrier; a carrier 2→a secondary carrier of thecarrier 1; and a carrier 3→a secondary carrier of the carrier 1.

In addition, the device 100 may not include the carrier grouping unit1004, that is, the processing circuit 101 does not execute the abovementioned function of grouping the carriers. Instead, a related spectrummanagement device groups the carriers and provides a result of thegrouping the carriers to the device 100.

The channel detection parameter generating unit 1001 generates at leastone set of channel detection parameters to be used by the user equipmentto detect whether a channel is idle, for each group of carriers obtainedby grouping. Multiple sets of channel detection parameters aregenerated, to provide flexibility of proper selection to the userequipment. Especially in a case that the same channel detectionparameter is generated for all user equipment in a cell (cell-specific),the presence of multiple sets of channel detection parameters providesbetter adaptability to different user equipment, thereby achieving abalance between accuracy of channel detection and signaling overhead.

In another aspect, the channel detection parameter generating unit 1001may generate at least one set of channel detection parameters for eachof the user equipment, respectively (UE-specific). In this case, thegenerated channel detection parameters may be based on a particularstatus of the user equipment, thereby improving accuracy of channeldetection.

The same channel detection parameter may be set for all carriers in eachgroup of carriers, however, which is not limited thereto. For each groupof carriers, the channel detection parameter for the primary carrier maybe different from the channel detection parameter for the secondarycarrier. For example, channel detection on the primary carrier is morecomplex than channel detection on the secondary carrier, and the channeldetection parameter for the primary carrier is set stricter than thechannel detection parameter for the secondary carrier, thereby savingpower consumption of channel detection. In practice, different channeldetection parameters may be set for all carriers in each group ofcarrier, thereby further improving accuracy of the channel detection.

The manner for channel detection, i.e., detection of whether a channelbeing idle, includes energy detection or characteristic detection. Theenergy detection refers to detecting whether a signal is transmitted ona channel, and the characteristic detection refers to detecting whichtype of communication device is occupying the channel. Thecharacteristic detection includes preamble detection and PLMN+PSS/SSSdetection. The preamble detection may be used to detect whether a WiFisignal is being transmitted, and the PLMN+PSS/SSS detection is used todetect whether there is an LTE signal and which type of LTE signal isbeing transmitted, which is applicable to the 4G Similarly, the channeldetection described here is also applicable to the future 5G or a moreadvanced wireless communication system. In the following description,the energy detection is taken as an example, however, it should beunderstood that the technology is also applicable to the characteristicdetection.

The channel detection may be implemented in a manner of listen beforetalk (LBT). The LBT refers to checking whether a channel is idle byclear channel assessment (CCA) before using the channel or the carrier.For example, the CCA may determine whether the channel is occupied basedon a result of energy detection on the channel. In a case that thechannel detection is the energy detection, each set of channel detectionparameters includes at least one of a type of the energy detection and athreshold value of the energy detection. The threshold value of theenergy detection is used to determine whether a channel is occupiedduring the energy detection. For example, it is considered that thechannel is occupied in a case that a result of energy detectionindicates that a value of accumulated energy is higher than thethreshold value. The type of the energy detection is used to indicate aspecific manner of the energy detection. For example, the type of theenergy detection includes: energy detection not involving randomback-off, energy detection involving random back-off and having a fixedcontention window size (CWS) and energy detection involving randomback-off and having a variable contention window size.

FIG. 3 is a schematic diagram showing a type of the energy detection,and (a), (b) and (c) in FIG. 3 show the three types described aboverespectively. In the type (a), data transmission is performed directlyafter the energy detection indicates that the channel is idle. In thetypes (b) and (c), random back-off and additional defer are performedafter an initial detection phase ends. Energy detection is alsoperformed during a duration of the random back-off, and back-off isperformed in the duration by providing a random back-off counter (alsoabbreviated as a counter). Counting of the random back-off counter isinterrupted in a case that the energy detection indicates that thechannel is occupied. The random back-off counter is set based on thecontention window size. In the type (b), the contention window size isfixed. In the type (c), the contention window size is variable. Adetection period is set for the energy detection. For example, in type(b) and (c), the detection period includes an initial detection phase, arandom back-off phase and an additional defer phase.

The energy detection operation performed by the user equipment may beconfigured by setting energy detection parameters for each group ofcarriers. For example, in the energy detection, for a primary carrier, atype of the energy detection may be set to be the energy detectioninvolving random back-off and having a variable contention window size,and a threshold value for determining whether a channel is idle is setto be low; and for a secondary carrier, a type of the energy detectionmay be set to be the energy detection not involving random back-off, anda threshold value for determining whether a channel is idle is set to behigh.

FIG. 4 shows an example of a signaling configuration of the carriergrouping information and the energy detection parameters, in which,carriers 1, 2 and 4 are a group of carriers, and carriers 3, 30 and 31are another group of carriers. Carriers 1 and 3 are primary carriers,and remaining carriers are secondary carriers. The type (c) of energydetection is used for the primary carriers, the type (c) of energydetection is also used for the secondary carrier 4, and the type (a) ofenergy detection is used for other secondary carriers than the secondarycarrier 4.

The uplink scheduling grant generating unit 1003 generates an uplinkscheduling grant for each group of carriers. As an example, the uplinkscheduling grant corresponds to one carrier, that is, the uplinkscheduling grant schedules the PUSCH on one carrier. However, the uplinkscheduling grant is valid for all carriers in the group of carriers. Inother words, upon receiving an uplink scheduling grant for schedulingone carrier, the user equipment extends, based on the carrier groupinginformation, the uplink scheduling grant to other carriers in a group ofcarriers to which the one carrier belongs, that is, it is consideredthat the base station schedules all the carriers in the group ofcarriers for the user equipment. Alternatively, as another example, theuplink scheduling grant may be changed to schedule multiple carriers inthe group of carriers. For example, a new field is added in the existinguplink scheduling grant.

In this way, as long as a channel corresponding to one carrier in thegroup of carriers is idle, the user equipment may perform datatransmission with the carrier, thereby improving usage efficiency ofresources in the unlicensed frequency band.

As shown in a dashed line block in FIG. 1, the device 100 may furtherinclude: a transceiving unit 102, configured to transmit the carriergrouping information and the channel detection parameters, andsubsequently transmit the uplink scheduling grant to the user equipment.The carrier grouping information and the channel detection parametersare transmitted in a licensed frequency band. In the embodiment, thetransceiving unit 102 transmits the uplink scheduling grant in thelicensed frequency band. In a case that there are multiple groups ofcarriers, the transceiving unit 102 transmits multiple uplink schedulinggrants correspondingly, that is, the transceiving unit 102 notifies theuser equipment that the user equipment can perform uplink datatransmission with multiple carriers.

The device 100 according to the embodiment uplink schedules the group ofcarriers rather than a single carrier, thereby improving usageefficiency of resources in the unlicensed frequency band. In addition,the device 100 schedules uplink transmission resources on multiplecarriers for the user equipment simultaneously, so that the userequipment can transmit uplink data on multiple carriers in theunlicensed frequency band, that is, implement carrier aggregation in theunlicensed frequency band.

Second Embodiment

In the embodiment, the transceiving unit 102 transmits the uplinkscheduling grant in the unlicensed frequency band. In view of this, theprocessing circuit 101 is further configured to detect whether a channelin the unlicensed frequency band is idle. This is because thetransceiving unit 102 can transmit the uplink scheduling grant only in acase that the channel is idle. As shown in FIG. 5, besides the channeldetection parameter generating unit 1001, the grouping informationgenerating unit 1002 and the uplink scheduling grant generating unit1003 described in the first embodiment, the processing circuit 101further includes a channel detecting unit 1005 configured to detectwhether a channel in the unlicensed frequency band is idle. It should benoted that although not shown in FIG. 5, the processing circuit 101 mayfurther include the carrier grouping unit 1004 described in the firstembodiment.

The channel detection parameter generating unit 1001 is furtherconfigured to generate the channel detection parameters used by thechannel detecting unit 1005 to perform channel detection for a group ofcarriers.

Similar to the first embodiment, the channel detection includes energydetection or characteristic detection. The energy detection refers todetecting whether a signal is transmitted on a channel, and thecharacteristic detection refers to detecting which type of communicationdevice is occupying the channel. The characteristic detection includespreamble detection and PLMN+PSS/SSS detection. The preamble detectionmay be used to detect whether a WiFi signal is being transmitted, andthe PLMN+PSS/SSS detection is used to detect whether there is an LTEsignal and which type of LTE signal is being transmitted, which isapplicable to the 4G Likewise, the channel detection described here isalso applicable to the future 5G or a more advanced wirelesscommunication system.

In a case that the channel detection is the energy detection, thechannel detection parameter includes at least one of a type of theenergy detection and a threshold value of the energy detection. Thethreshold value of the energy detection is used to determine whether achannel is being occupied during the energy detection. For example, thetype of the energy detection includes energy detection not involvingrandom back-off, energy detection involving random back-off and having afixed contention window size, and energy detection involving randomback-off and having a variable contention window size. Reference is madeto the first embodiment for specific description of the type of energydetection, which is not repeated here anymore.

Generally, channel detection performed by the device 100 is more complexthan channel detection performed by the user equipment, and the channeldetection parameter is set stricter than the channel detection parametergenerated for the user equipment, thereby improving accuracy of channeldetection at the base station side. For example, in the energydetection, the energy detection involving random back-off and having thevariable contention window size may be used, and a threshold value fordetermining whether a channel is idle is set to be low.

In an example, the channel detecting unit 1005 performs channeldetection on all carriers in each group of carriers respectively, and ina case that the channel detection indicates that a channel is idle, thetransceiving unit 102 transmits the uplink scheduling grant on a carriercorresponding to the channel. In a case that there are multiple groupsof carriers, the transceiving unit 102 transmits the uplink schedulinggrant on multiple carriers corresponding to idle channels respectively.

In another example, before the carriers in the unlicensed frequency aregrouped, the channel detecting unit 1005 may perform channel detectionon multiple carriers (such as all carriers) in the unlicensed frequencyband, and select carriers which are indicated to be idle during thechannel detection, to be used by the transceiving unit 102 to transmitthe uplink scheduling grant. In this example, the carrier grouping unit1004 groups the carriers based on the idle carriers on which the uplinkscheduling grant is transmitted, for example, the idle carrier serves asa primary carrier in a group of carriers.

The channel detecting unit 1005 may perform channel detection on allcarriers when performing the channel detection described above. In otherwords, channel detection is performed on all carriers in parallel in atotal preset channel detection time period. The preset channel detectiontime periods for the multiple carriers have the same end time. In theembodiment, the end time is for example a time when a downlink timeslotcomes.

In an example, in order to reduce calculation complexity and lighten theprocessing load, the channel detecting unit 1005 may have a structureshown in FIG. 6. In FIG. 6, the channel detecting unit 1005 includes: adetecting unit 501, configured to perform channel detection of whether achannel being idle on a carrier; and a triggering unit 502, configuredto, in a case that it is detected during the channel detection on afirst carrier in each group of carriers that the channel is occupied,trigger the detecting unit 501 to perform channel detection on a secondcarrier other than the first carrier in the group of carriers. The“first” and “second” here are only used to distinguish differentcarriers, and do not represent a specific order. For example, the firstcarrier and the second carrier may be selected randomly. The duration ofthe channel detection on the first carrier refers to a time period afterthe channel detection on the first carrier is started. The time periodmay be less than or equal to the preset channel detection time period.

In other words, the channel detecting unit 1005 does not perform channeldetection on the first carrier and the second carrier simultaneously,and perform cascaded channel detection on the first carrier and thesecond carrier. For example, in a case that although the channeldetection on the first carrier is not completed, it may be judged thatthe channel is being occupied, channel detection on the second carrieris started. Exemplarily, channel detection on the first carrier can becontinued in this case. For example, multiple detecting units 501 may beprovided to perform channel detection on the first carrier and on thesecond carrier respectively. In this case, a duration of the channeldetection on the second carrier is shorter than a duration of thechannel detection on the first carrier, but the two durations have thesame end time (in the embodiment, the end time is for example a timewhen a downlink timeslot comes).

In addition, as shown in dashed line block in FIG. 6, the channeldetecting unit 1005 may further include a control unit 503, configuredto control the triggering unit 502 to trigger to perform channeldetection on all carriers in each group of carriers sequentially, sothat channel detection is performed on a next carrier only in a casethat channel detection on a previous carrier indicates that the previouscarrier is occupied, until all the carriers in the group of carriers ora downlink timeslot comes. Channel detection on all carriers in eachgroup of carriers has different start time, but has the same end time.FIG. 7 shows an example of an operation of the channel detecting unit1005. Assuming a group of carriers includes three carriers 1 to 3, and ahorizontal axis represents a time axis. Channel detection on carrier 1is started at a time t1, and channel detection on carrier 2 is startedor triggered at a time t2 in a case of determining at the time t2 thatthe channel detection on carrier 1 indicates that the channel isoccupied. Similarly, channel detection on carrier 3 is started ortriggered at a time t3 in a case of determining that the channel isoccupied during the channel detection on carrier 2 such as at the timet3. Channel detection on carriers 1 to 3 is continued until a downlinktimeslot comes. In a case that a result of channel detection indicatesthere are multiple idle carriers at the end time, one of the multipleidle carriers is selected for data transmission. The one carrier may beselected randomly or according to a predetermined rule, for example,according to channel quality, a load status or the like. On thecontrary, channel detection would not be performed on carrier 2 andcarrier 3, in a case that during the channel detection on carrier 1 thechannel is not detected to be occupied. Therefore, preferably, for eachgroup of carriers, at most one carrier corresponding to an idle channelcan be used for data transmission in consideration of signalingoverhead.

It can be seen that calculation overhead caused by channel detection canbe reduced by the cascaded channel detection manner described above.

In a case that the channel detecting unit 1005 finds an idle carrier byperforming channel detection on each group of carriers, the transceivingunit 102 transmits the uplink scheduling grant for the group of carriersto the user equipment with the idle carrier. As described above, theuplink scheduling grant may be with respect to one carrier in the groupof carriers but valid for all carriers in the group of carriers,alternatively, the uplink scheduling grant may be uplink schedulinggrant including scheduling for multiple carriers in the group ofcarriers.

The device 100 according to the embodiment performs uplink scheduling onthe group of carriers rather than a single carrier, thereby improvingusage efficiency of resources in the unlicensed frequency band. Inaddition, the device 100 schedules uplink transmission resources onmultiple carriers simultaneously for the user equipment, so that theuser equipment can transmit uplink data on multiple carriers in theunlicensed frequency band, that is, implement carrier aggregation in theunlicensed frequency band.

Third Embodiment

FIG. 8 is a block diagram of a device 200 for wireless communicationsaccording to an embodiment of the present disclosure, the device 200includes at least one processing circuit 201 configured to: determine,based on carrier grouping information for an unlicensed frequency bandand an uplink scheduling grant for the unlicensed frequency bandreceived from a base station, a group of carriers on which channeldetection is to be performed; and perform channel detection on a carrierin the determined group of carriers using channel detection parametersreceived from the base station.

The device 200 may be located for example at a user equipment side in awireless communication system. For example, the device 200 may beimplemented as a mobile terminal (such as a smart phone, a tabletpersonal computer (PC), a laptop PC, a portable game terminal, aportable/dongle mobile router and a digital camera device) or anon-board terminal (such as a car navigation terminal). The device 200may also be implemented as a terminal (also referred to as a machinetype communication (MTC) terminal) for performing machine-to-machine(M2M) communication. In addition, the device 200 may be a wirelesscommunication module (such as an integrated circuit module including asingle wafer) installed on each terminal described above.

In addition, FIG. 8 further shows an example of functional modules ofthe processing circuit 201. As shown in FIG. 8, the processing circuit201 includes a carrier group determining unit 2001 and a channeldetecting unit 2002. It should be understood that the functional modulesmay be implemented by processing circuits respectively, or may all beimplemented by one processing circuit, or may be implemented as a partof a processing circuit. Alternatively, each functional module may beimplemented by multiple processing circuits. In other words,implementation of the functional modules is not limited. The processingcircuit 201 may be for example a central processing unit (CPU), amicroprocessor, an integrated circuit module or the like having dataprocessing capability. A structure and a function of the device 200 aredescribed in detail below with reference to FIG. 8.

In a case that the user equipment in which the device 200 is located isto perform data transmission using the unlicensed frequency band, theuser equipment first transmits a request to the base station andreceives an uplink scheduling grant from the base station, and then usesuplink transmission resources on the unlicensed frequency band based onthe uplink scheduling grant. Since other user equipment may be using thecarrier scheduled by the uplink scheduling grant, the user equipmentneeds to perform channel detection before transmitting data, and cantransmit data with the carrier scheduled by the uplink scheduling grantonly in a case that the channel detection indicates that the channel isidle. Correspondingly, the user equipment further needs to acquirechannel detection parameters configured by the base station for the userequipment.

In addition, in the embodiment, the user equipment also acquires carriergrouping information from the base station. As described above, in orderto improve usage efficiency of resources, the base station groups thecarriers into multiple groups and generates an uplink scheduling grantfor each group of carriers. Therefore, the uplink scheduling grantreceived by the user equipment is valid for the group of carriers, evenin a case that the uplink scheduling grant may only include anindication for one carrier.

For example, the carrier group determining unit 2001 determines carrier1 as the scheduled carrier from the uplink scheduling grant, anddetermines that carrier 2 and carrier 3 are in the same group ofcarriers as carrier 1 based on the carrier grouping information. Thechannel detecting unit 2002 performs channel detection on carriers 1 to3 using the channel detection parameters for the group of carriersreceived from the base station. In a case that any one of the carriers 1to 3 is idle, the user equipment can perform data transmission with theidle carrier.

In an example, the user equipment may receive multiple uplink schedulinggrants from the base station. Each of the uplink scheduling grants isvalid for one group of carriers. As shown in FIG. 9, two uplinkscheduling grants are received by the user equipment, and the carriergrouping determining unit 2001 determines carriers 1 to 3 and carriers 4to 6 as two scheduled groups of carriers based on the carrier groupinginformation, and the channel detecting unit 2002 performs channeldetection on the carriers 1 to 3 and the carriers 4 to 6 respectively,and detects that carrier 1 is idle among the carriers 1 to 3 and carrier5 is idle among the carrier 4 to 6. Therefore, the user equipmentperforms uplink data transmission with carrier 1 and carrier 5. Itshould be understood that, FIG. 9 only shows an example, and the numberof uplink scheduling grants received by the user equipment is notlimited to 2, and may be another number.

Channel detection parameters for carriers in a group of carriers may bethe same with each other or may be different from each other. Forexample, a channel detection parameter for a primary carrier isdifferent from a channel detection parameter for a secondary carrier. Inone group of carriers, a priority level for the user equipment to usethe primary carrier to perform data transmission is higher than apriority level for the user equipment to use the secondary carrier toperform data transmission. In addition, multiple sets of channeldetection parameters may be generated for one group of carriers, and theprocessing circuit 201 may be correspondingly configured to select oneset of channel detection parameters from the at least one set of channeldetection parameters based on a priority level of a service of the userequipment, to perform channel detection. Accordingly, as shown in FIG.10, the processing circuit 201 may further include a selecting unit 2003configured to suitably select channel detection parameters.

The channel detection (that is, detection of whether a channel beingidle) includes energy detection or characteristic detection. The energydetection refers to detecting whether a signal is being transmitted on achannel, and the characteristic detection refers to detecting which typeof communication device is occupying the channel. The characteristicdetection includes preamble detection and PLMN+PSS/SSS detection. Thepreamble detection may be used to detect whether a WiFi signal is beingtransmitted, and the PLMN+PSS/SSS detection is used to detect whetherthere is an LTE signal and which type of LTE signal is beingtransmitted, which is applicable to the 4G Likewise, the channeldetection described here is also applicable to the future 5G or a moreadvanced wireless communication system. In the following description,the energy detection is taken as an example, however, it should beunderstood that the technology is also applicable to the characteristicdetection.

In a case that the channel detection is the energy detection, the energydetection parameters may include at least one of a type of energydetection and a threshold value of the energy detection. The thresholdvalue of energy detection is used to determine whether a channel isbeing occupied during the energy detection. The type of the energydetection includes energy detection not involving random back-off,energy detection involving random back-off and having a fixed contentionwindow size, and energy detection involving random back-off and having avariable contention window size. The energy detection parameters havebeen described in detail in the first embodiment, which are not repeatedhere anymore.

The channel detecting unit 2002 may perform channel detection on each ofcarriers in the group of carriers. Preset channel detection time periodsfor multiple carriers have the same end time. In the embodiment, the endtime may be for example a subframe starting boundary of a physicaluplink shared channel (PUSCH).

In an example, in order to reduce calculation complexity and lightenprocessing load, the channel detecting unit 2002 may perform cascadeddetection on carriers in the group of carriers. As shown in FIG. 11, thechannel detecting unit 2002 includes: a detecting unit 601, configuredto perform channel detection of whether a channel being idle on acarrier; and a triggering unit 602, configured to, in a case that it isdetected during the channel detection on a first carrier in each groupof carriers that a channel is occupied, trigger the detecting unit 601to perform channel detection on a second carrier other than the firstcarrier in the group of carriers. The “first” and “second” here are onlyused to distinguish different carriers, and do not represent a specificorder. Functions of the detecting unit 601 and the triggering unit 602are basically the same as those of the detecting unit 501 and thetriggering unit 502 described in the second embodiment respectively. Inthe example, the channel detecting unit 2002 executes cascaded channeldetection on each group of carriers respectively, and the user equipmentwould select a carrier, a channel detection result for which indicatesthat the corresponding channel is idle when the channel detection timeperiod ends, so as to perform data transmission. Exemplarily, thechannel detection on the first carrier is continued when channeldetection on the second carrier is triggered. In this case, a durationof the channel detection on the second carrier is less than a durationof the channel detection on the first carrier, but the two durationshave the same end time (in the embodiment, the end time is for examplethe subframe starting boundary of a PUSCH).

For example, in a case that the channel detection is the energydetection, the detecting unit 601 may be configured to determine that acarrier is occupied in a case that a value of energy accumulated in theenergy detection on the carrier in a predetermined time period exceeds athreshold value for determining whether a channel is occupied in energydetection. The predetermined time period may be set to be for example 9microseconds or longer.

In addition, as shown in a dashed line block in FIG. 11, the channeldetecting unit 2002 may further include a control unit 603, configuredto control the triggering unit 602 to trigger to perform channeldetection on all carriers in each group of carrier sequentially, so thatchannel detection is performed on a next carrier only in a case thatchannel detection on a previous carrier indicates that the previouscarrier is occupied, until a physical uplink shared channel (PUSCH)starts and all carriers in the group of carriers are traversed beforethe PUSCH starts. Before the PUSCH starts here means before the subframestarting boundary of the PUSCH. In the example, the channel detectingunit 2002 performs channel detection on all carriers in the group ofcarriers in a cascaded manner before the PUSCH starts, thereby reducingcalculation amount required for the channel detection. In the example,channel detection on the carriers in each group of carriers hasdifferent start time, but has the same end time. In a case that a resultof the channel detection at the end time indicates that multiplecarriers are idle, one of the multiple carriers is selected for datatransmission. For example, a primary carrier is selected in a case thatthe primary carrier is idle, and a secondary carrier is selectedrandomly or according to a predetermined rule in a case that the primarycarrier is not idle. The predetermined rule may be determined based on afactor such as channel quality.

In addition, the control unit 603 may further determine a primarycarrier and a secondary carrier in the group of carriers based on thecarrier grouping information. The control unit 603 takes the primarycarrier as the first carrier, and the triggering unit 602 triggers toperform channel detection on the secondary carriers sequentially in acase that the channel detection on the primary carrier indicates thatthe primary carrier is occupied. In other words, the control unit 603controls to perform channel detection on the primary carrier first, andperform channel detection on the secondary carriers in a case that thechannel detection on the primary carrier indicates that the primarycarrier is occupied. An order of performing channel detection on thesecondary carriers may be determined randomly, or may be determined bythe control unit 603 based on for example a frequency band position orthe like.

As described above, the channel detection on the primary carrier may bemore complex than the channel detection on the secondary carrier, andthe channel detection parameters for the primary carrier is set stricterthan channel detection parameter for the secondary carrier. In a casethat the channel detection is the energy detection, for example, a typeof energy detection on the primary carrier may be energy detectioninvolving random back-off, and a type of energy detection on thesecondary carrier is energy detection not involving random back-off.

The energy detection involving random back-off includes an initialdetection phase, a random back-off phase and an additional defer phase.As shown in FIG. 12, energy detection on the primary carrier indicatesthat the primary carrier is occupied in one of the following cases: acase where energy detection in the initial detection stage indicatesthat a channel is not idle, a case where counting of a counter isinterrupted in the random back-off stage, and a case where the energydetection in the additional defer stage indicates that a channel is notidle. In FIG. 12, since a value of energy accumulated from t1 to t2 inthe initial detection phase already exceeds the related threshold valueof energy detection, the primary carrier 1 is considered to be occupiedat t2, and the triggering unit 602 triggers to perform energy detectionon the secondary carrier 2. The carrier 2 is also considered to beoccupied in a case that a value of energy accumulated from t2 to t3exceeds the threshold value, and the triggering unit 602 triggers toperform energy detection on the secondary carrier 3. A minimum durationin which energy is accumulated for each carrier may be 9 microseconds,that is, whether the carrier is occupied can be determined after theduration.

As shown in a dashed line block in FIG. 8, the device 200 may furtherinclude: a transceiving unit 202, configured to receive at least one setof channel detection parameters to be used by the user equipment toperform channel detection, the carrier grouping information and theuplink scheduling grant from the base station. The transceiving unit 202may receive the channel detection parameters, the carrier groupinginformation and the uplink scheduling grant in a licensed frequencyband. Alternatively, the transceiving unit 202 may receive the uplinkscheduling grant in the unlicensed frequency band.

The device 200 according to the embodiment may perform channel detectionon carriers in the group of carriers based on the carrier groupinginformation, thereby improving a probability that an idle channel isdetected and improving usage efficiency of resources of the unlicensedfrequency band.

Fourth Embodiment

FIG. 12 is a block diagram of a spectrum management device 300 accordingto an embodiment of the present disclosure. As shown in FIG. 12, thespectrum management device 300 includes: at least one processing circuit301 configured to group carriers in an unlicensed frequency band; and atransmitting unit 302, configured to transmit carrier groupinginformation on grouping of the carriers to a base station. Theprocessing circuit 301 may be for example a central processing unit(CPU), a microprocessor, an integrated circuit module and the likehaving data processing capability.

As described above, the carriers may be grouped by the base station, ormay also be grouped by the spectrum management device. In theembodiment, the spectrum management device 300 groups the carriers andtransmits the carrier grouping information to each base station.

As an example, the processing circuit 301 may group the carriers basedon at least one of a frequency band location of each carrier, a usagestatus of each carrier, an amount of data to be transmitted for eachservice of the user equipment, and information in a geographicallocation database. The usage status of each carrier may be stored in thespectrum management device 300. The amount of data to be transmitted foreach service of the user equipment may be provided to the base stationfor example based on a buffer status report (BSR), and the base stationreports the amount of data to the spectrum management device 300.

For example, in a case that the frequency band locations of two carriersare close or adjacent to each other, the two carriers may have similarchannel characteristics, and therefore, the two carriers may be groupedinto the same group. In addition, the usage status of the carrierindicates a load status on the carrier, for example, a carrier withlight load may be selected to be grouped. In another aspect, forexample, in a case that there is a large amount of data to betransmitted by the user equipment, a carrier with light load may beselected to be grouped. In addition, the processing circuit 301 may alsotake a geographical location of the user equipment into consideration byreferring to information in the geographical location database. Forexample, in a case that user equipment which is using a carrier toperform data transmission is far away from user equipment for whichuplink transmission resources are to be scheduled currently, the carriermay be selected.

In an example, the processing circuit 301 may select a primary carrierand then select a secondary carrier allocated to the primary carrier, togroup the carriers. In a group of carriers, a priority level for theuser equipment to use the primary carrier to perform data transmissionis higher than a priority level for the user equipment to use thesecondary carrier to perform data transmission. In practice, theprocessing circuit 301 may also group the carriers in another particularmanner. For example, the carriers to be grouped into the same group areselected, and then a primary carrier and a secondary carrier aredesignated, which are not limited here.

The spectrum management device 300 according to the embodiment providesinformation on the grouping of carriers to the base station, therebyreducing processing load of the base station, and reducing signalingoverhead due to not requiring to provide a usage status of the carrierto the base station.

Fifth Embodiment

FIG. 14 shows a block diagram of a channel detection device 400according to an embodiment of the present disclosure. The channeldetection device is used to perform channel detection on multiplecarriers in an unlicensed frequency band. As shown in FIG. 14, thechannel detection device includes at least one processing circuit 401.The multiple carriers includes a first carrier and a second carrier, andthe processing circuit 401 is configured to perform channel detection ofwhether a channel being idle on the first carrier, and trigger channeldetection of whether a channel being idle on the second carrier in acase that it is detected during the channel detection on the firstcarrier that the channel is occupied.

In addition, FIG. 14 further shows an example of functional modules ofthe processing circuit 401. As shown in FIG. 14, the processing circuit401 includes a detecting unit and a trigging unit 4002. The detectingunit 4001 is configured to perform channel detection of whether achannel being idle on a carrier. The triggering unit 4002 is configuredto trigger the detecting unit 4001 to perform channel detection on thesecond carrier in a case that the channel detection on the first carrierby the detecting unit 4001 indicates that a channel is occupied. Itshould be understood that the functional modules may be implemented byprocessing circuits respectively, or may all be implemented by oneprocessing circuit, or may be implemented as a part of a processingcircuit. Alternatively, each functional module may be implemented bymultiple processing circuits. In other words, implementation of thefunctional modules is not limited. The processing circuit 401 may be forexample a central processing unit (CPU), a microprocessor, an integratedcircuit module and the like having data processing ability. A structureand a function of the device 400 are described in detail below withreference to FIG. 14.

The channel detection device 400 triggers channel detection on a nextcarrier based on an indication that a channel is occupied during thechannel detection on a previous carrier, and in this way, cascadedchannel detection can be implemented, thereby reducing processing loadof the channel detection. As shown in a dashed line block in FIG. 14,the processing circuit 401 may further include a control unit 4003configured to, in a case that there are multiple carriers to bedetected, control the triggering unit 4002 to trigger the detecting unit4001 to perform channel detection on all carriers sequentially. Channeldetection is performed on a next carrier only in a case that channeldetection on a previous carrier indicates that a channel is occupied,until the plurality of carriers are traversed or a time period forchannel detection is over. In this case, the previous carrier isequivalent to the first carrier and the next carrier is equivalent tothe second carrier.

The time period for channel detection here is for example a presetchannel detection time period. In a case that channel detection isperformed on all carriers in parallel respectively, preset channeldetection time periods for the carriers have the same end time. In acase that the channel detection is performed in a cascaded way in theembodiment, channel detection on all carriers has different start time,since a start time of the channel detection on the next carrier is laterthan a start time of the channel detection on the previous carrier.However, the channel detection on the carriers has the same end time.For uplink channel detection, the end time is for example a subframestarting boundary of a physical uplink shared channel. For downlinkchannel detection, the end time is for example a time when a downlinktimeslot comes.

In an example, the multiple carriers are grouped into multiple groups ofcarriers, and the channel detection device 400 performs the cascadedchannel detection described above on each group of carriers.Specifically, for each group of carriers, the control unit 4003 controlsthe triggering unit 4002 to trigger the detecting unit 4001 to performchannel detection on carriers in the group of carriers sequentially.Channel detection is performed on a next carrier only in a case that thechannel detection on a previous carrier indicates that the channel isoccupied, until all the carriers in the group of carriers are traversedor a time period for channel detection is over. Therefore, for eachgroup of carriers, in a case that channel detection on one carrier inthe group of carriers indicates that the channel is idle, the idlechannel may be used for data transmission, thereby improving usageefficiency of resources of the unlicensed frequency band. In a case thatthere are multiple carriers in the group of carriers, channelscorresponding to which are indicated to be idle during the channeldetection, one carrier is selected from the multiple carriers randomlyor according to a predetermined rule, for data transmission. Thepredetermined rule may be for example determined based on a factor suchas channel quality.

In a case that user equipment includes the above channel detectiondevice 400, if the user equipment receives uplink scheduling grants formultiple groups of carriers, the channel detection device 400 mayperform the cascaded channel detection on each group of carriers. Theuser equipment transmits data with a carrier which is idle in thechannel detection on each group of carriers at a time when a subframestarting boundary of the PUSCH starts.

In addition, the detecting unit 4001 may perform channel detection ondifferent carriers using the same channel detection parameter ordifferent channel detection parameters, which depends on actualrequirements or setting.

The channel detection includes energy detection or characteristicdetection. The energy detection refers to detecting whether there is asignal being transmitted on a channel, and the characteristic detectionrefers to detecting which type of communication device is occupying achannel. The characteristic detection includes preamble detection andPLMN+PSS/SSS detection. The preamble detection may be used to detectwhether a WiFi signal is being transmitted, and the PLMN+PSS/SSSdetection is used to detect whether there is an LTE signal and whichtype of LTE signal is being transmitted, which is applicable to the 4GLikewise, the channel detection described here is also applicable to thefuture 5G or a more advanced wireless communication system. In thefollowing description, the energy detection is taken as an example,however, it should be understood that the technology is also applicableto the characteristic detection.

In a case that the channel detection is the energy detection, an energydetection parameter may include at least one of a type of energydetection and a threshold value of energy detection. The threshold valueof the energy detection is used to determine whether a channel isoccupied during the energy detection. The type of the energy detectionincludes energy detection not involving random back-off, energydetection involving random back-off and having a fixed contention windowsize and energy detection involving random back-off and having avariable contention window size. The energy detection parameter has beendescribed in detail in the first embodiment, which is not repeated hereanymore.

The detecting unit 4001 is configured to determine that a channelcorresponding to a detected carrier is occupied, in a case that a valueof energy accumulated in energy detection on the detected carrier in apredetermined time period exceeds a threshold value of energy detectionfor the detected carrier which is used to determine whether the channelis occupied. For example, predetermined time periods are different fordifferent carriers, and/or predetermined time periods are different fordifferent detection phases for the same carrier. Generally, accuracy ofenergy detection increases with an increase of the predetermined timeperiod, and the setting of the predetermined time period is related tothe energy detection parameter.

As an example, the energy detection involving random back-off includesan initial detection phase, a random back-off phase and an additiondefer phase. It is indicated during the energy detection involvingrandom back-off that the carrier is occupied in at least one case of thefollowing cases: a case that energy detection in the initial detectionphase indicates that the channel is not idle, a case that counting ofthe counter is interrupted in the random back-off phase, and a case thatenergy detection in the additional defer phase indicates that thechannel is not idle. Specifically, as shown in FIG. 3, if a value ofaccumulated energy detected at a certain time of the initial detectionphase exceeds a threshold value, it is determined that the channel isoccupied. In this case, the triggering unit 4002 may trigger thedetecting unit 4001 to detect a next carrier. In another aspect, if itis detected in the initial detection phase that the channel is notoccupied, the channel detection proceeds to the random back-off phase. Arandom back-off counter is set based on a contention window size (CWS).The counting of the random back-off counter is interrupted in a casethat the energy detection indicates that the channel is occupied. Inthis case, the triggering unit 4002 may trigger the detecting unit 4001to detect a next carrier. It can be seen in the example that thepredetermined time periods during which the energy is accumulated may beset to be different from each other in the initial detection phase andin the random back-off phase.

In another example, each group of carriers includes a primary carrierand a secondary carrier. In a group of carriers, a priority level to usethe primary carrier to perform data transmission is higher than apriority level to use the secondary carrier to perform datatransmission. For each group of carriers, the control unit 4003 controlsthe triggering unit 4002 to trigger the detecting unit 4001 to performchannel detection on the primary carrier and the secondary carriersequentially, until all carriers in the group of carriers are traversedor a time period for channel detection is over. That is, the channeldetection device 400 performs channel detection on the primary carrierfirst, and then performs channel detection on the secondary carrier onlyin a case that the channel detection on the primary carrier indicatesthat the channel is occupied.

In a case that the channel detection on the primary carrier indicatesthat the channel is occupied, and the subsequent channel detection onone of the secondary carriers indicates that the channel is idle, thecontrol unit 4003 selects the secondary carrier corresponding to theidle channel for data transmission. Different types of energy detectionmay be performed on the primary carrier and the secondary carrier. Forexample, a type of energy detection on the primary carrier is the energydetection involving random back-off, and a type of energy detection onthe secondary carrier is the energy detection not involving randomback-off.

The above channel detection device 400 may be used for detecting anuplink channel, or may be used for detecting a downlink channel. Thecarriers are detected in a cascaded way, thereby effectively reducingprocessing load of the channel detection. The channel detection device400 may be applied to each device according to the first embodiment tothe third embodiment.

In addition, user equipment including the channel detection device 400and a base station including the channel detection device 400 arefurther provided according to the embodiment.

Sixth Embodiment

In the process of describing the device for a wireless communicationsystem and the channel detection device in the embodiments describedabove, obviously, some processing and methods are also disclosed.Hereinafter, an overview of the methods is given without repeating somedetails disclosed above. However, it should be noted that, although themethods are disclosed in a process of describing the device for awireless communication system and the channel detection device, themethods do not certainly employ or are not certainly executed by theaforementioned components. For example, the embodiments of the devicefor a wireless communication system and the channel detection device maybe partially or completely implemented with hardware and/or firmware,the method for wireless communications described below may be executedby a computer-executable program completely, although the hardwareand/or firmware of the device for a wireless communication system andthe channel detection device can also be used in the methods.

FIG. 15 is a flow diagram of a method for wireless communicationsaccording to an embodiment of the present disclosure, and the methodincludes: for at least one group of carriers in an unlicensed frequencyband, generating at last one set of channel detection parameters for useby user equipment to detect whether a channel is idle (S12), wherein theat least one group of carriers are acquired by grouping at least a partof carriers in the unlicensed frequency band; generating carriergrouping information indicating a result of the grouping of the carriers(S13); and generating an uplink scheduling grant for the at least onegroup of carriers (S16).

In step S12, the same channel detection parameter or different channeldetection parameters may be generated for all carriers in each group ofcarriers. In an example, each group of carriers includes a primarycarrier and a secondary carrier. In a group of carriers, a prioritylevel for the user equipment to use the primary carrier to perform datatransmission is higher than a priority level for the user equipment touse the secondary carrier to perform data transmission. In this case, achannel detection parameter for the primary carrier may be differentfrom a channel detection parameter for the secondary carrier. Forexample, the channel detection on the primary carrier is more complexthan channel detection on the secondary carrier, and the channeldetection parameter for the primary carrier is set stricter than thechannel detection parameter for the secondary carrier. The carriergrouping information generated in step S13 may include for exampleinformation indicating a group to which a carrier belongs, andinformation indicating whether the carrier is a primary carrier or asecondary carrier in the group. In this way, the user equipment maydetermine other carriers which are in the same group as the carrierbased on the carrier.

In step S12, at least one set of channel detection parameters may begenerated for each of the user equipment, alternatively, at least oneset of channel detection parameters which are commonly used by userequipment in a cell is generated for the cell.

Detection of whether a channel being idle may include energy detection.The channel detection parameters include for example at least one of atype of energy detection and a threshold value of energy detection. Thethreshold value of the energy detection is used to determine whether achannel is occupied during the energy detection. The type of energydetection may include energy detection not involving random back-off,energy detection involving random back-off and having a fixed contentionwindow size, and energy detection involving random back-off and having avariable contention window size. In addition, detection of whether thechannel being idle may also include characteristic detection. Thecharacteristic detection includes for example preamble detection andPLMN+PSS/SSS.

The uplink scheduling grant generated for each group of carriers in stepS16 is valid for all carriers in the group of carriers.

In addition, as shown in dashed line block in FIG. 5, the above methodmay further include a step S11: grouping carriers in unlicensedfrequency band. For example, in step S11, the carriers may be groupedbased on at least one of a frequency band location of each carrier, ausage status of each carrier, an amount of data to be transmitted foreach service of the user equipment, and information in a geographicallocation database. The usage status of each carrier may be obtained forexample by at least one of the following manners: being measured by thebase station, being provided by a related spectrum management device, orbeing provided by a related geographical location database.

In step S11, a primary carrier may be selected and then a secondarycarrier allocated to the primary carrier may be selected, for groupingthe carriers. In practice, the carriers may be grouped in other manners.

In addition, as shown in a dashed line block in FIG. 15, the abovemethod may further include a step S14: transmitting the carrier groupinginformation and the channel detection parameters to the user equipment.The carrier grouping information and the channel detection parametersare transmitted to the user equipment in a licensed frequency band. Theabove method further includes a step S17: transmitting the uplinkscheduling grant to the user equipment. The uplink scheduling grant maybe transmitted to the user equipment in the licensed frequency band.

In an example, step S17 may include transmitting the uplink schedulinggrant to the user equipment in the unlicensed frequency band. In thiscase, the above method further includes a step S15, detecting whether achannel in the unlicensed frequency band is idle. Although not shown inFIG. 15, the above method may further include generating channeldetection parameters used in channel detection for each group ofcarriers, before performing step S15. In step S15, channel detection canbe performed on all carriers in each group of carriers respectively. Inaddition, step S15 may also be performed before step S11, that is,channel detection is performed on multiple carriers for example allcarriers in the unlicensed frequency band before grouping the carriersin the unlicensed frequency band. A carrier which is indicated to beidle in the channel detection is selected in a subsequent step totransmit the uplink scheduling grant.

In an example, step S15 may also be implemented as: performing channeldetection on a first carrier in each group of carriers; and performingchannel detection on a second carrier other than the first carrier inthe group of carriers in a case that it is detected during the channeldetection on the first carrier that a channel is occupied. Step S15 mayfurther include: triggering channel detection on all carriers in eachgroup of carriers sequentially, so that channel detection is performedon a next carrier only in a case that channel detection on a previouscarrier indicates that the previous carrier is occupied, until adownlink timeslot comes or all carriers in the group of carriers aretraversed.

In the above method, the carriers are grouped, and each group ofcarriers rather than a single carrier is scheduled, thereby improvingusage efficiency of resources in the unlicensed frequency band, andmultiple carriers are scheduled for the user equipment, therebyimproving communication quality and capacity.

FIG. 16 shows a flow diagram of a method for wireless communicationsaccording to an embodiment of the present disclosure. The methodincludes: determining, based on carrier grouping information for anunlicensed frequency band and an uplink scheduling grant for theunlicensed frequency band received from a base station, a group ofcarriers on which channel detection is to be performed (S22); andperforming channel detection on a carrier in the determined group ofcarriers using channel detection parameters received from the basestation (S24).

The channel detection performed in step S24 may be energy detection, andthe channel detection parameter may include at least one of a type ofenergy detection and a threshold value of energy detection. Thethreshold value of the energy detection is used to determine whether achannel is occupied during the energy detection. The type of energydetection may include energy detection not involving random back-off,energy detection involving random back-off and having a fixed contentionwindow size and energy detection involving random back-off and having avariable contention window size.

In addition, as shown in a dashed line block in FIG. 16, the abovemethod may further include a step S21: receiving, from the base station,at least one set of channel detection parameters to be used by userequipment to perform the channel detection, the carrier groupinginformation and the uplink scheduling grant. The channel detectionparameters, the carrier grouping information and the uplink schedulinggrant may be received in the licensed frequency band. Alternatively, theuplink scheduling grant may be received in the unlicensed frequencyband.

The above method may further include a step S23: selecting a set ofchannel detection parameters from among the at least one set of channeldetection parameters based on a priority level of a service of the userequipment, to perform the channel detection.

In step S24, channel detection may be performed on all carriers in eachgroup of carriers respectively. In addition, step S24 may also beimplemented as: for each group of carriers, performing channel detectionon a first carrier in the group of carriers; and triggering to performenergy detection on a second carrier, in a case that it is detectedduring the channel detection on the first carrier that a channel isoccupied. Step S24 may further include: for each group of carriers,triggering to perform channel detection on all carriers in the group ofcarriers sequentially, so that channel detection is performed on a nextcarrier only in a case that the channel detection on a previous carrierindicates that the previous carrier is occupied, until a physical uplinkshared channel (PUSCH) starts and all the carriers in the group ofcarriers are traversed before the PUSCH starts.

In addition, a primary carrier and a secondary carrier in the group ofcarriers may be determined based on the carrier grouping information instep S24. In a group of carriers, a priority level for the userequipment to use the primary carrier to perform data transmission ishigher than a priority level for the user equipment to use the secondarycarrier to perform data transmission. The primary carrier is taken asthe first carrier, and channel detection on the secondary carriers istriggered sequentially in a case that the channel detection on theprimary carrier indicates that the primary carrier is occupied.

As an example, the channel detection is energy detection, a type of theenergy detection on the primary carrier is energy detection involvingrandom back-off, and a type of the energy detection on the secondarycarrier is energy detection not involving random back-off. The energydetection involving the random back-off includes an initial detectionphase, a random back-off phase and an additional defer phase. The energydetection on the primary carrier indicates that the primary carrier isoccupied in at least one of the following cases: a case where energydetection in the initial detection stage indicates that a channel is notidle, a case where counting of a counter is interrupted in the randomback-off stage, and a case where the energy detection in the additionaldefer stage indicates that a channel is not idle. In the channeldetection, in a case that a value of energy accumulated by the energydetection on a carrier in a predetermined time period exceeds athreshold value for determining whether the channel is occupied in theenergy detection, it is determined that the carrier is occupied.

In the method, the user equipment may perform channel detection oncarriers in the group of carriers based on the carrier groupinginformation, thereby improving a probability that an idle channel isdetected, and improving usage efficiency of resources in the unlicensedfrequency band.

FIG. 17 shows a channel detection method for performing channeldetection on multiple carriers in an unlicensed frequency band accordingto an embodiment of the present disclosure. The multiple carriersinclude a first carrier and a second carrier. The method includes:performing channel detection of whether a channel being idle on thefirst carrier (S31); and triggering channel detection of whether achannel being idle on the second carrier in a case that it is detectedduring channel detection on the first carrier that the channel isoccupied (S32).

The above method further includes performing channel detection on allcarriers of the multiple carriers sequentially. Channel detection isperformed on a next carrier only in a case that channel detection on aprevious carrier indicates that the channel is occupied, until themultiple carriers are traversed or a time period for channel detectionends.

In an example, multiple carriers are grouped into multiple groups ofcarriers, and each group of carriers includes a primary carrier and asecondary carrier. A priority level of using the primary carrier toperform data transmission is higher than a priority level of using thesecondary carrier to perform data transmission. Channel detection isperformed on the primary carrier and all secondary carriers in eachgroup of carriers sequentially, until all carriers in the group ofcarriers are traversed or a time period for channel detection ends.

When channel detection on the primary carrier indicates that the channelis occupied, and channel detection on one of the secondary carriersindicates that the channel is idle, the secondary carrier correspondingto the idle channel is selected to perform data transmission.

The channel detection may be energy detection. In a case that a value ofenergy accumulated in energy detection on the detected carrier in apredetermined time period exceeds a threshold value of energy detectionfor the detected carrier which is used to determine whether the channelis occupied, it is determined that the channel corresponding to thecarrier is occupied. The predetermined time periods are different fordifferent carriers, and/or the predetermined time periods are differentfor different detection phases for the same carrier.

An energy detection parameter may include at least one of a type ofenergy detection and a threshold value of energy detection. Thethreshold value of the energy detection is used to determine whether achannel is occupied during the energy detection. The type of the energydetection may include energy detection not involving random back-off,energy detection involving random back-off and having a fixed contentionwindow size, and energy detection involving random back-off and having avariable contention window size. Channel detection parameters may be thesame or different for the different carriers. For example, a type ofenergy detection on the primary carrier is energy detection involvingrandom back-off, and a type of energy detection on the secondary carrieris energy detection not involving random back-off.

In an example, the energy detection involving random back-off includesan initial detection phase, a random back-off phase and an additionaldefer phase. It is indicated during the energy detection involvingrandom back-off that the carrier is occupied in at least one of thefollowing cases: a case that energy detection in the initial detectionphase indicates that the channel is not idle, a case that counting ofthe counter is interrupted in the random back-off phase, and a case thatenergy detection in the additional defer phase indicates that thechannel is not idle.

In the method, the carriers are detected in a cascaded manner, therebyeffectively reducing processing load of channel detection.

It is to be noted that, the above methods can be used separately or inconjunction with each other. The details have been described in detailin the first to fifth embodiments, and are not repeatedly describedhere.

For convenience of understanding, FIG. 18 and FIG. 19 show examples ofan information procedure between a base station and one of the userequipment. The base station (eNB) includes for example a device 100, theuser equipment (UE) includes for example a device 200. It should beunderstood that the information procedure is not limited. It should benoted that although two UEs are shown at the left side and the rightside, the two UEs are the same UE substantively. Such an illustration isjust to distinguish whether a licensed frequency or an unlicensedfrequency is used in communication between the eNB and the UE.

FIG. 18 shows an example of an information procedure for cross-carrierscheduling. In FIG. 18, the UE transmits data in an unlicensed frequencyband, and the UE transmits a request to the eNB and transmits a bufferstatus report (BSR). The BSR indicates the amount of data to betransmitted by the UE or a priority level. Upon receiving the BSR, theeNB determines that the UE is to perform uplink transmission on twocarriers. The eNB groups the carriers, for example, carriers 1 to 6 areselected to be grouped into two groups {1, 2, 3} and {4, 5, 6}. The eNBgenerates channel detection parameters such as energy detectionparameters for each group of carriers, and transmits the channeldetection parameters along with carrier grouping information (not shownin FIG. 18) to the UE. The eNB transmits two generated uplink (UL)scheduling grants (corresponding to the groups of carriers {1, 2, 3} and{4, 5, 6} respectively) to the user equipment. The above communicationis performed in the licensed frequency band. Upon receiving the uplinkscheduling grants, the UE performs channel detection on the scheduledgroup of carriers based on the carrier grouping information and theuplink scheduling grants. In a case that at least one carrier is idle ineach group of carriers, the UE performs data transmission on theselected idle carrier. The UE performs channel detection for examplewith the cascaded channel detection method described above.

FIG. 19 shows an example of an information procedure of self-carrierscheduling. A difference of FIG. 19 from FIG. 18 is in that the eNBperforms channel detection on each group of carriers after grouping thecarriers, and transmits the UL scheduling grants on a carrier, which isindicated to be idle in the channel detection, in the unlicensedfrequency band. The eNB may also perform channel detection for examplewith the cascaded channel detection method described above.

In addition, FIG. 20 shows another example of an information procedureof self-carrier scheduling. A difference of FIG. 20 from FIG. 19 is inthat the eNB performs channel detection on all carriers and groups thecarriers based on a result of the channel detection. Specifically, theeNB selects N (N is the number of carriers to be scheduled for the UE bythe eNB) carriers which are indicated to be idle in the channeldetection and groups the N carriers, and transmits an UL schedulinggrant corresponding to a group of carriers on the carrier. Similarly,the eNB transmits channel detection parameters for each group ofcarriers in the licensed frequency band before transmitting the uplinkscheduling grant.

APPLICATION EXAMPLE

The technology in the present disclosure can be applied into variousproducts. For example, the spectrum management device 300 may beimplemented as any type of servers, such as a tower server, a rackmounted server and a blade server. The spectrum management device 300may be a control module (such as an integrated circuit module includinga single wafer, and a card or blade (blade) inserted into a slot of theblade server) mounted on a server.

In addition, a base station described above can be implemented as anytype of evolved node B (eNB), such as a macro eNB and a small eNB. Thesmall eNB such as a pico eNB, micro eNB and a home (femto-cell) eNB mayhave a smaller coverage range than a macro cell. Alternatively, the basestation may also be implemented as any other type of base stations, suchas a NodeB and a base transceiver station (BTS). The base station mayinclude a body (also referred to as a base station device) configured tocontrol wireless communications; and one or more remote radio heads(RRHs) arranged in a different position from the body. In addition,various types of terminals described below may operate as a base stationby temporarily or semi-persistently executing the function of the basestation.

[Application Example Regarding Base Station]

First Application Example

FIG. 21 is a block diagram illustrating a first example of a schematicconfiguration of an eNB to which the technology of the presentdisclosure may be applied. An eNB 800 includes one or more antennas 810and a base station apparatus 820. Each antenna 810 and the base stationapparatus 820 may be connected to each other via an RF cable.

Each of the antennas 810 includes a single or multiple antenna elements(such as multiple antenna elements included in an MIMO antenna), and isused for the base station apparatus 820 to transmit and receive radiosignals. The eNB 800 may include the multiple antennas 810, asillustrated in FIG. 20. For example, the multiple antennas 810 may becompatible with multiple frequency bands used by the eNB 800. AlthoughFIG. 21 illustrates the example in which the eNB 800 includes themultiple antennas 810, the eNB 800 may also include a single antenna810.

The base station apparatus 820 includes a controller 821, a memory 822,a network interface 823, and a radio communication interface 825.

The controller 821 may be, for example, a CPU or a DSP, and operatesvarious functions of a higher layer of the base station apparatus 820.For example, the controller 821 generates a data packet from data insignals processed by the radio communication interface 825, andtransfers the generated packet via the network interface 823. Thecontroller 821 may bundle data from multiple base band processors togenerate the bundled packet, and transfer the generated bundled packet.The controller 821 may have logical functions of performing control suchas radio resource control, radio bearer control, mobility management,admission control, and scheduling. The control may be performed incorporation with an eNB or a core network node in the vicinity. Thememory 822 includes RAM and ROM, and stores a program that is executedby the controller 821, and various types of control data (such as aterminal list, transmission power data, and scheduling data).

The network interface 823 is a communication interface for connectingthe base station apparatus 820 to a core network 824. The controller 821may communicate with a core network node or another eNB via the networkinterface 823. In that case, the eNB 800, and the core network node orthe other eNB may be connected to each other through a logical interface(such as an S1 interface and an X2 interface). The network interface 823may also be a wired communication interface or a radio communicationinterface for radio backhaul. If the network interface 823 is a radiocommunication interface, the network interface 823 may use a higherfrequency band for radio communication than a frequency band used by theradio communication interface 825.

The radio communication interface 825 supports any cellularcommunication scheme such as Long Term Evolution (LTE) and LTE-Advanced,and provides radio connection to a terminal positioned in a cell of theeNB 800 via the antenna 810. The radio communication interface 825 maytypically include, for example, a baseband (BB) processor 826 and an RFcircuit 827. The BB processor 826 may perform, for example,encoding/decoding, modulating/demodulating, andmultiplexing/demultiplexing, and performs various types of signalprocessing of layers (such as L1, medium access control (MAC), radiolink control (RLC), and a packet data convergence protocol (PDCP)). TheBB processor 826 may have a part or all of the above-described logicalfunctions instead of the controller 821. The BB processor 826 may be amemory that stores a communication control program, or a module thatincludes a processor and a related circuit configured to execute theprogram. Updating the program may allow the functions of the BBprocessor 826 to be changed. The module may be a card or a blade that isinserted into a slot of the base station apparatus 820. Alternatively,the module may also be a chip that is mounted on the card or the blade.Meanwhile, the RF circuit 827 may include, for example, a mixer, afilter, and an amplifier, and transmits and receives radio signals viathe antenna 810.

The radio communication interface 825 may include the multiple BBprocessors 826, as illustrated in FIG. 21. For example, the multiple BBprocessors 826 may be compatible with multiple frequency bands used bythe eNB 800. The radio communication interface 825 may include themultiple RF circuits 827, as illustrated in FIG. 21. For example, themultiple RF circuits 827 may be compatible with multiple antennaelements. Although FIG. 21 illustrates the example in which the radiocommunication interface 825 includes the multiple BB processors 826 andthe multiple RF circuits 827, the radio communication interface 825 mayalso include a single BB processor 826 or a single RF circuit 827.

In the eNB 800 shown in FIG. 21, the transceiving unit 102 describedwith reference to FIG. 1 may be implemented by the radio communicationinterface 825. At least a part of the functions may be implemented bythe controller 821. For example, the controller 821 may execute theuplink scheduling grant for each group of carriers by executing thefunction of the processing circuit 101.

(Second Application Example)

FIG. 22 is a block diagram illustrating a second example of a schematicconfiguration of an eNB to which the technology of the presentdisclosure may be applied. An eNB 830 includes one or more antennas 840,a base station apparatus 850, and an RRH 860. Each antenna 840 and theRRH 860 may be connected to each other via an RF cable. The base stationapparatus 850 and the RRH 860 may be connected to each other via a highspeed line such as an optical fiber cable.

Each of the antennas 840 includes a single or multiple antenna elements(such as multiple antenna elements included in an MIMO antenna), and isused for the RRH 860 to transmit and receive radio signals. The eNB 830may include the multiple antennas 840, as illustrated in FIG. 22. Forexample, the multiple antennas 840 may be compatible with multiplefrequency bands used by the eNB 830. Although FIG. 22 illustrates theexample in which the eNB 830 includes the multiple antennas 840, the eNB830 may also include a single antenna 840.

The base station apparatus 850 includes a controller 851, a memory 852,a network interface 853, a radio communication interface 855, and aconnection interface 857. The controller 851, the memory 852, and thenetwork interface 853 are the same as the controller 821, the memory822, and the network interface 823 described with reference to FIG. 21.

The radio communication interface 855 supports any cellularcommunication scheme such as LTE and LTE-Advanced, and provides radiocommunication to a terminal positioned in a sector corresponding to theRRH 860 via the RRH 860 and the antenna 840. The radio communicationinterface 855 may typically include, for example, a BB processor 856.The BB processor 856 is the same as the BB processor 826 described withreference to FIG. 21, except the BB processor 856 is connected to the RFcircuit 864 of the RRH 860 via the connection interface 857. The radiocommunication interface 855 may include the multiple BB processors 856,as illustrated in FIG. 22. For example, the multiple BB processors 856may be compatible with multiple frequency bands used by the eNB 830.Although FIG. 22 illustrates the example in which the radiocommunication interface 855 includes the multiple BB processors 856, theradio communication interface 855 may also include a single BB processor856.

The connection interface 857 is an interface for connecting the basestation apparatus 850 (radio communication interface 855) to the RRH860. The connection interface 857 may also be a communication module forcommunication in the above-described high speed line that connects thebase station apparatus 850 (radio communication interface 855) to theRRH 860.

The RRH 860 includes a connection interface 861 and a radiocommunication interface 863.

The connection interface 861 is an interface for connecting the RRH 860(radio communication interface 863) to the base station apparatus 850.The connection interface 861 may also be a communication module forcommunication in the above-described high speed line.

The radio communication interface 863 transmits and receives radiosignals via the antenna 840. The radio communication interface 863 maytypically include, for example, the RF circuit 864. The RF circuit 864may include, for example, a mixer, a filter, and an amplifier, andtransmits and receives radio signals via the antenna 840. The radiocommunication interface 863 may include multiple RF circuits 864, asillustrated in FIG. 22. For example, the multiple RF circuits 864 maysupport multiple antenna elements. Although FIG. 22 illustrates theexample in which the radio communication interface 863 includes themultiple RF circuits 864, the radio communication interface 863 may alsoinclude a single RF circuit 864.

In the eNB 830 shown in FIG. 22, the transceiving unit 102 describedwith reference to FIG. 1 may be implemented by the radio communicationinterface 855 and/or the radio communication interface 863. At least apart of functions may be implemented by the controller 851. For example,the controller 851 may execute the uplink scheduling grant for eachgroup of carriers by executing the function of the processing circuit101.

[Application Example Regarding User Equipment]

First Application Example

FIG. 23 is a block diagram illustrating an example of a schematicconfiguration of a smartphone 900 to which the technology of the presentdisclosure may be applied. The smartphone 900 includes a processor 901,a memory 902, a storage 903, an external connection interface 904, acamera 906, a sensor 907, a microphone 908, an input device 909, adisplay device 910, a speaker 911, a radio communication interface 912,one or more antenna switches 915, one or more antennas 916, a bus 917, abattery 918, and an auxiliary controller 919.

The processor 901 may be, for example, a CPU or a system on a chip(SoC), and controls functions of an application layer and another layerof the smartphone 900. The memory 902 includes RAM and ROM, and stores aprogram that is executed by the processor 901, and data. The storage 903may include a storage medium such as a semiconductor memory and a harddisk. The external connection interface 904 is an interface forconnecting an external device such as a memory card and a universalserial bus (USB) device to the smartphone 900.

The camera 906 includes an image sensor such as a charge coupled device(CCD) and a complementary metal oxide semiconductor (CMOS), andgenerates a captured image. The sensor 907 may include a group ofsensors such as a measurement sensor, a gyro sensor, a geomagneticsensor, and an acceleration sensor. The microphone 908 converts soundsthat are input to the smartphone 900 to audio signals. The input device909 includes, for example, a touch sensor configured to detect touchonto a screen of the display device 910, a keypad, a keyboard, a button,or a switch, and receives an operation or an information input from auser. The display device 910 includes a screen such as a liquid crystaldisplay (LCD) and an organic light-emitting diode (OLED) display, anddisplays an output image of the smartphone 900. The speaker 911 convertsaudio signals that are output from the smartphone 900 to sounds.

The radio communication interface 912 supports any cellularcommunication scheme such as LET and LTE-Advanced, and performs radiocommunication. The radio communication interface 912 may typicallyinclude, for example, a BB processor 913 and an RF circuit 914. The BBprocessor 913 may perform, for example, encoding/decoding,modulating/demodulating, and multiplexing/demultiplexing, and performsvarious types of signal processing for radio communication. Meanwhile,the RF circuit 914 may include, for example, a mixer, a filter, and anamplifier, and transmits and receives radio signals via the antenna 916.The radio communication interface 912 may be a one chip module havingthe BB processor 913 and the RF circuit 914 integrated thereon. Theradio communication interface 912 may include the multiple BB processors913 and the multiple RF circuits 914, as illustrated in FIG. 23.Although FIG. 23 illustrates the example in which the radiocommunication interface 912 includes the multiple BB processors 913 andthe multiple RF circuits 914, the radio communication interface 912 mayalso include a single BB processor 913 or a single RF circuit 914.

Furthermore, in addition to a cellular communication scheme, the radiocommunication interface 912 may support another type of radiocommunication scheme such as a short-distance wireless communicationscheme, a near field communication scheme, and a radio local areanetwork (LAN) scheme. In that case, the radio communication interface912 may include the BB processor 913 and the RF circuit 914 for eachradio communication scheme.

Each of the antenna switches 915 switches connection destinations of theantennas 916 among multiple circuits (such as circuits for differentradio communication schemes) included in the radio communicationinterface 912.

Each of the antennas 916 includes a single or multiple antenna elements(such as multiple antenna elements included in an MIMO antenna), and isused for the radio communication interface 912 to transmit and receiveradio signals. The smartphone 900 may include the multiple antennas 916,as illustrated in FIG. 23. Although FIG. 23 illustrates the example inwhich the smartphone 900 includes the multiple antennas 916, thesmartphone 900 may also include a single antenna 916.

Furthermore, the smartphone 900 may include the antenna 916 for eachradio communication scheme. In that case, the antenna switches 915 maybe omitted from the configuration of the smartphone 900.

The bus 917 connects the processor 901, the memory 902, the storage 903,the external connection interface 904, the camera 906, the sensor 907,the microphone 908, the input device 909, the display device 910, thespeaker 911, the radio communication interface 912, and the auxiliarycontroller 919 to each other. The battery 918 supplies power to blocksof the smartphone 900 illustrated in FIG. 23 via feeder lines, which arepartially shown as dashed lines in the figure. The auxiliary controller919 operates a minimum necessary function of the smartphone 900, forexample, in a sleep mode.

In the smart phone 900 shown in FIG. 23, the transceiving unit 201described with reference to FIG. 8 may be implemented by the radiocommunication interface 912. At least a part of functions may also berealized by the processor 901 or the auxiliary controller 919. Forexample, the processor 901 or the auxiliary controller 919 may performchannel detection on the group of carriers rather than a single carrierby executing the function of the processing circuit 201, therebyimproving resource usage efficiency in the unlicensed frequency band.

(Second Application Example)

FIG. 24 is a block diagram illustrating an example of a schematicconfiguration of a car navigation apparatus 920 to which the technologyof the present disclosure may be applied. The car navigation apparatus920 includes a processor 921, a memory 922, a global positioning system(GPS) module 924, a sensor 925, a data interface 926, a content player927, a storage medium interface 928, an input device 929, a displaydevice 930, a speaker 931, a radio communication interface 933, one ormore antenna switches 936, one or more antennas 937, and a battery 938.

The processor 921 may be, for example, a CPU or a SoC, and controls anavigation function and another function of the car navigation apparatus920. The memory 922 includes RAM and ROM, and stores a program that isexecuted by the processor 921, and data.

The GPS module 924 uses GPS signals received from a GPS satellite tomeasure a position (such as latitude, longitude, and altitude) of thecar navigation apparatus 920. The sensor 925 may include a group ofsensors such as a gyro sensor, a geomagnetic sensor, and an air pressuresensor. The data interface 926 is connected to, for example, anin-vehicle network 941 via a terminal that is not shown, and acquiresdata generated by the vehicle, such as vehicle speed data.

The content player 927 reproduces content stored in a storage medium(such as a CD and a DVD) that is inserted into the storage mediuminterface 928. The input device 929 includes, for example, a touchsensor configured to detect touch onto a screen of the display device930, a button, or a switch, and receives an operation or an informationinput from a user. The display device 930 includes a screen such as aLCD or an OLED display, and displays an image of the navigation functionor content that is reproduced. The speaker 931 outputs sounds of thenavigation function or the content that is reproduced.

The radio communication interface 933 supports any cellularcommunication scheme such as LTE and LTE-Advanced, and performs radiocommunication. The radio communication interface 933 may typicallyinclude, for example, a BB processor 934 and an RF circuit 935. The BBprocessor 934 may perform, for example, encoding/decoding,modulating/demodulating, and multiplexing/demultiplexing, and performsvarious types of signal processing for radio communication. Meanwhile,the RF circuit 935 may include, for example, a mixer, a filter, and anamplifier, and transmits and receives radio signals via the antenna 937.The radio communication interface 933 may also be a one chip module thathas the BB processor 934 and the RF circuit 935 integrated thereon. Theradio communication interface 933 may include the multiple BB processors934 and the multiple RF circuits 935, as illustrated in FIG. 24.Although FIG. 24 illustrates the example in which the radiocommunication interface 933 includes the multiple BB processors 934 andthe multiple RF circuits 935, the radio communication interface 933 mayalso include a single BB processor 934 or a single RF circuit 935.

Furthermore, in addition to a cellular communication scheme, the radiocommunication interface 933 may support another type of radiocommunication scheme such as a short-distance wireless communicationscheme, a near field communication scheme, and a radio LAN scheme. Inthat case, the radio communication interface 933 may include the BBprocessor 934 and the RF circuit 935 for each radio communicationscheme.

Each of the antenna switches 936 switches connection destinations of theantennas 937 among multiple circuits (such as circuits for differentradio communication schemes) included in the radio communicationinterface 933.

Each of the antennas 937 includes a single or multiple antenna elements(such as multiple antenna elements included in an MIMO antenna), and isused for the radio communication interface 933 to transmit and receiveradio signals. The car navigation apparatus 920 may include the multipleantennas 937, as illustrated in FIG. 24. Although FIG. 24 illustratesthe example in which the car navigation apparatus 920 includes themultiple antennas 937, the car navigation apparatus 920 may also includea single antenna 937.

Furthermore, the car navigation apparatus 920 may include the antenna937 for each radio communication scheme. In that case, the antennaswitches 936 may be omitted from the configuration of the car navigationapparatus 920.

The battery 938 supplies power to blocks of the car navigation apparatus920 illustrated in FIG. 24 via feeder lines that are partially shown asdashed lines in the figure. The battery 938 accumulates power suppliedform the vehicle.

In the car navigation apparatus 920 shown in FIG. 24, the transceivingunit 201 described with reference to FIG. 8 may be implemented by theradio communication interface 933. At least a part of functions may alsobe realized by the processor 921. For example, the processor 921 mayperform channel detection on the group of carriers rather than a singlecarrier by executing the function of the processing circuit 201, therebyimproving resource usage efficiency in the unlicensed frequency band.

The technology of the present disclosure may also be realized as anin-vehicle system (or a vehicle) 940 including one or more blocks of thecar navigation apparatus 920, the in-vehicle network 941, and a vehiclemodule 942. The vehicle module 942 generates vehicle data such asvehicle speed, engine speed, and trouble information, and outputs thegenerated data to the in-vehicle network 941.

The basic principle of the present invention has been described above inconjunction with particular embodiments. However, as can be appreciatedby those ordinarily skilled in the art, all or any of the steps orcomponents of the method and device according to the invention can beimplemented in hardware, firmware, software or a combination thereof inany computing device (including a processor, a storage medium, etc.) ora network of computing devices by those ordinarily skilled in the art inlight of the disclosure of the invention and making use of their generalcircuit designing knowledge or general programming skills.

Moreover, the present invention further discloses a program product inwhich machine-readable instruction codes are stored. The aforementionedmethods according to the embodiments can be implemented when theinstruction codes are read and executed by a machine.

Accordingly, a memory medium for carrying the program product in whichmachine-readable instruction codes are stored is also covered in thepresent invention. The memory medium includes but is not limited to softdisc, optical disc, magnetic optical disc, memory card, memory stick andthe like.

In the case where the present application is realized by software orfirmware, a program constituting the software is installed in a computerwith a dedicated hardware structure (e.g. the general computer 2500shown in FIG. 25) from a storage medium or network, wherein the computeris capable of implementing various functions when installed with variousprograms.

In FIG. 25, a central processing unit (CPU) 2501 executes variousprocessing according to a program stored in a read-only memory (ROM)2502 or a program loaded to a random access memory (RAM) 2503 from amemory section 2508. The data needed for the various processing of theCPU 2501 may be stored in the RAM 2503 as needed. The CPU 2501, the ROM2502 and the RAM 2503 are linked with each other via a bus 2504. Aninput/output interface 2505 is also linked to the bus 2504.

The following components are linked to the input/output interface 2505:an input section 2506 (including keyboard, mouse and the like), anoutput section 2507 (including displays such as a cathode ray tube(CRT), a liquid crystal display (LCD), a loudspeaker and the like), amemory section 2508 (including hard disc and the like), and acommunication section 2509 (including a network interface card such as aLAN card, modem and the like). The communication section 2509 performscommunication processing via a network such as the Internet. A driver2510 may also be linked to the input/output interface 2505. If needed, aremovable medium 2511, for example, a magnetic disc, an optical disc, amagnetic optical disc, a semiconductor memory and the like, may beinstalled in the driver 2510, so that the computer program readtherefrom is installed in the memory section 2508 as appropriate.

In the case where the foregoing series of processing is achieved bysoftware, programs forming the software are installed from a networksuch as the Internet or a memory medium such as the removable medium2511.

It should be appreciated by those skilled in the art that the memorymedium is not limited to the removable medium 2511 shown in FIG. 25,which has program stored therein and is distributed separately from theapparatus so as to provide the programs to users. The removable medium2511 may be, for example, a magnetic disc (including floppy disc(registered trademark)), a compact disc (including compact discread-only memory (CD-ROM) and digital versatile disc (DVD), a magnetooptical disc (including mini disc (MD)(registered trademark)), and asemiconductor memory. Alternatively, the memory medium may be the harddiscs included in ROM 2502 and the memory section 2508 in which programsare stored, and can be distributed to users along with the device inwhich they are incorporated.

To be further noted, in the apparatus, method and system according tothe invention, the respective components or steps can be decomposedand/or recombined. These decompositions and/or recombinations shall beregarded as equivalent schemes of the invention. Moreover, the aboveseries of processing steps can naturally be performed temporally in thesequence as described above but will not be limited thereto, and some ofthe steps can be performed in parallel or independently from each other.

Finally, to be further noted, the term “include”, “comprise” or anyvariant thereof is intended to encompass nonexclusive inclusion so thata process, method, article or device including a series of elementsincludes not only those elements but also other elements which have beennot listed definitely or an element(s) inherent to the process, method,article or device. Moreover, the expression “comprising a(n) . . . ” inwhich an element is defined will not preclude presence of an additionalidentical element(s) in a process, method, article or device comprisingthe defined element(s)” unless further defined.

Although the embodiments of the invention have been described above indetail in connection with the drawings, it shall be appreciated that theembodiments as described above are merely illustrative but notlimitative of the invention. Those skilled in the art can make variousmodifications and variations to the above embodiments without departingfrom the spirit and scope of the invention. Therefore, the scope of theinvention is defined merely by the appended claims and theirequivalents.

The invention claimed is:
 1. A user equipment for performing channeldetection on a plurality of carriers in an unlicensed frequency band foruplink transmissions, the user equipment comprising: a processingcircuit, the plurality of carriers comprises a first carrier and asecond carrier, and the processing circuit is configured to: performchannel detection selected from the group consisting of a first type ofthe channel detection and a second type of the channel detection that isdifferent from the first type of the channel detection; perform thefirst type of the channel detection on the first carrier to confirmwhether the first carrier is available; wherein a type of the channeldetection performed on the first carrier is different from the type ofthe channel detection performed on the second carrier; and in responseto a condition that the first type of the channel detection is performedon the first carrier, perform the second type of the channel detectionon the second carrier to confirm whether the second carrier isavailable.
 2. The user equipment according to claim 1, wherein at leastone of the first type of the channel detection or the second type of thechannel detection comprises energy detection.
 3. The user equipmentaccording to claim 2, wherein, in said at least one of the first type ofthe channel detection or the second type of the channel detection, theenergy detection is performed using a threshold.
 4. The user equipmentaccording to claim 2, wherein, in said at least one of the first type ofthe channel detection or the second type of the channel detection, theenergy detection is performed using a contention window.
 5. The userequipment according to claim 4, wherein, in said at least one of thefirst type of the channel detection or the second type of the channeldetection, the contention window has a variable size.